Online businesses could be in breach of the Data Protection Act (DPA) if they don't make it clear to customers that personal data is being collected by cookies.
Cookies invade the privacy of surfers by covertly gathering personal data, according to the European Parliament which has classed them as 'spyware'.
And the IC has backed the amendments and warned UK companies that they risk breaching the DPA by using cookies.
"The issue is this: is personal data being collected and is it transparent to the punter? If it isn't, then there is a problem with the DPA," said Philip Jones, assistant commissioner at the IC.
But the marketing and advertising industry is lobbying European governments to drop the amendments, claiming they will set back the growth of ecommerce.
The UK online advertising industry will lose £187m, according to the Internet Advertising Bureau and the Advertising Association.
"Advertising plays an important role in keeping website content/usage free by defraying the costs of setting up and maintaining website content," said Andrew Brown, director general of the Advertising Association.
"If ecommerce sites are forced to redesign the architecture of sites, this will be at a huge financial cost, placing unnecessary burdens upon industry," he added.
But the claims were dismissed by the IC. "All the shroud waving from the internet and marketing industry about costs has been somewhat exaggerated," said Jones.
Cotton seedling freezes to death as Chang'e-4 shuts down for the Moon's 14-day lunar night
Fortnite easily out-earns PUBG, Assassin's Creed Odyssey and Red Dead Redemption 2 in 2018
Meteor showers as a service will be visible for about 100 kilometres in all directions
Saturn's rings only formed in the past 100 million years, suggests analysis of Cassini space probe data
New findings contradict conventional belief that Saturn's rings were formed along with the planet about 4.5 billion years ago